Kevin82

So I was doing an oil change for my c250 the other day and was going to clean the K&N air filter that came with the BMS Intake since it's been about 15,000 miles since I've cleaned it.

Upon doing so I saw that the bottom of the air filter was rubbing against some other part in the engine compartment causing the air filter to grind down and eventually create a HOLE in the air filter (see pics). I removed the BMS metal intake tubing to inspect to see if dirt entered the intake tube and saw that there was some specks of dirt that have accumulated.

So I decided to continue with my oil change and found that there were specks of grit/dirt in the oil filter when rubbing the oil between my hands, most likely caused by the air filter sucking in all the dirt from the tiny hole. Also on my oil drain pan there were some specks of grit also.

Anyone with a BMS Intake should check to see if your air filter is also rubbing to avoid any damage from dirt entering your engine. I've had the intake for 15,000 miles and who know how long I've been driving with a damaged air filter.

I did notice that when the engine is hot that the air filter vibrates vs when it's cold. BMS may need to create a braket to reduce the vibration. I could be wrong and maybe installed it incorrectly, but I'm hoping everyone can verify that this is the case. Thanks.

Edit: I also posted in sedan forums to see if users had same issues there: https://mbworld.org/forums/c-class-w...ml#post5555800

Kevin82

pictures continued. You can see where the light shines through the intake where the dirt can enter and also a pic of how dirty the interior of the intake port is:

aluo325

I hope they solve this problem soon. I was hoping to get this intake. Please keep us updated!

Kevin82

Seems like another user had the same rubbing issue in the sedan forums: https://mbworld.org/forums/c-class-w...ml#post5555800

Jon@BMS

When you set the filter before tightening the clamp just angle the filter a mm or two so it can't rub on anything. On the movement with the screw holding the bracket to the base of the airbox there should not be any movement. If there is perhaps you have installed the bracket wrong, etc.

If you need a replacement filter we have those for $40 shipped. We suggest cleaning or replacing them every 10-15k miles. If cleaning use a normal K&N cleaning kit.

DameMD

After reading this thread, I decided to take a look at my filter. I am also having rubbing issues however, I followed Terry's advice and moved the filter further away from the bottom of the Airbox where that hard metal/plastic square piece is rubbing the filter. I also added a 2in foam strip where the square metal piece is to prevent future rubbing. I have pics below of my filter too. I will chime back in after a few months to see if I am still rubbing. I will probably be replacing the filter anyway as I like to have a fresh filter. It would be nice to have a non-oiled filter option. I don't mind paying for a new filter every 10k-15k miles.

DameMD

Oh forgot to mention, I put the stock airbox back and did about a half hour worth of driving. Car was not as responsive and felt like it needed me to put the BMS filter back on. I did and also took advantage of setting my JB Beta to 100%. Car is a lot more fun to drive. I also did the throttle reset.

Kevin82

Make sure you replace the k&n filter before reinstalling. The picture looks like it could let in grit in your engine.

BlackjackM

Kevin82, thank you for pointing out this issue to us- I too am having the rubbing issue. Thankfully the intake has only been installed for about 1k miles but it still did a number on the filter. I readjusted the filter and crushed it a bit on the bottom to try and keep it from rubbing more. But now I will be checking it regularly.

The bottom line is that filter is too big for that space. Did you notice that when you adjust it upwards it now hits the engine cover? Also, it sucks that I have to crush some of it to keep it from rubbing, I'm sure that doesn't help airflow.

Jon@BMS

Much better for overall airflow and service life than reducing the filter diameter by 1/2" which would be the alternative.

DameMD

Terry - Off topic, do you, or could you provide a dry filter option? I really like the airflow of a dry filter like apex'i or something compared to the oil-filter provided by K&N. I am willing to pay more if need be.

PM me if you have other options :-)

Jon@BMS

Since the car does not have a MAF sensor I would not suggest a dry. But, if there is enough demand we could always custom do a batch of dry filters for it.

gtyard

Terry,
How do I order the replacement filter only. Your site only offers the complete kit

Jon@BMS

Easiest way if within the USA is to paypal $40 to orders@burgertuning.com and include "C250 replacement filter" in order notes.

AllEyesOnMe

Did anyone successfully re-adjust the filter position as guided and solve the issue with the filter rubbing? Just wondering if I should bother readjusting it at all seeing as how some people did not have success with it.

OCtheMIKE

I'm new to the forums, but wanted to chime in on this for my first post. I checked my filter out yesterday (installed for around 1500 miles) and it was definitely rubbing.

I tried angling the filter itself but when I felt underneath there was still contact with the metal piece. I also tried angling the metal tube but because of the bracket you don't have much play there. So I ended up just angling the filter as much as I could and placing some adhesive foam on the metal piece where I could clearly see the contact point from the scratches.

I'll check it again in a month or so. If its still tearing up the filter I'll have to resort to pushing in the filter to get the needed clearance.

Kevin82

Is your filter still rubbing?

dave405nyc

Just checked my BMS intake and it's rubbing too =(. I can see two small holes in the intake when passing it thru a light source. Put back my stock one while I decide what do with it.

AllEyesOnMe

Too bad us C250 guys are the minority, or else I'm sure there could've been a compromise if this issue generates enough heat.

Now just how many more C250 owners are going to purchase this product not knowing the innate issues they're going to be facing...

100degrees

About to pull the trigger on the intake but now this worries me. There's no way any adjustments can make it better?

DecemberHeat

I already pulled the trigger and now wonder would it be ok if I just flatten air filter area where it may touch to give me some 1/4 inches of space..

Kevin82

The thing is that when the engine bay gets hot the rubber part of where the intake filter is clamped will flex more easily so flattening the filter might not do the trick.

I do not recommend anyone purchase or use the intake until a smaller compatible filter is found or some sort of mounting piece is created to stop the intake vibrating.

J__

I have a sedan and posted this on the sedan section:

I checked mine today and same thing, rubbed through the filter. I have a different rub point as well, on the right hand side where the fins are in the bottom half of the filter box. It's rubbing there as well but not through yet.



the other rub point:


dust:



only been 3000km since install. Tried adjusting and rotating the angle but not much room to rotate. because of the engine cover.



SO, the possible solution i found:
ok so I did a bit of research and here's what I have. The specs for the filter provided my BMS is 76mm opening with 125mm top and bottom base, 165mm length. According to K&N filter size chart, this would work perfectly:

Filter model RU-5111
http://www.knfilters.com/search/prod...x?prod=RU-5111

of course it won't look as nice and flush as the one BMS provides but it won't rub and become useless. I haven't tried it yet but technically speaking it should be the perfect size.

BlackjackM

Has anyone NOT had rubbing issues yet? (Other than Terry, of course)